In recent years, display devices such liquid crystal display devices, Organic Electroluminescence display devices etc., for controlling the display gradation of each pixel using thin film transistors (TFT) are being developed. The realization of high definition display panels in these display devices is being required by reducing the area occupied by a pixel circuit arranged with a thin film transistor and condenser etc., in each pixel.
Consequently, a conventional liquid crystal display device has been proposed in which a condenser (retention volume) which holds the potential of a pixel electrode for a fixed period is formed in a side wall of a trench structure (groove structure) formed on a substrate, a drop in an aperture ratio is continually prevented by arranging the condenser in a narrow region on the substrate and the potential retaining characteristics of the pixel electrode are improved (for example, refer to patent document 1 [Japanese Published Unexamined Publication 2008-40399]).
However, as in the liquid crystal display device described above, In the case of forming a condenser using a side wall of a trench structure formed on a substrate, there was a problem whereby the burden on the manufacturing process increases because it is necessary to form a plurality of fine groves on a glass substrate formed with a thin film transistor.
The present invention attempts to solve the problem described above by forming a pixel circuit including a condenser which can hold a required electric charge without increasing the area occupied in each pixel in a simple manufacturing process and thereby provide a display device with high definition and improved display capabilities.